Estimation of Time of Death (TOD) of White-Tailed Deer: a Comparison of Three Indicators
Date of Graduation
Master of Science in Biology
Establishment of time of death (TOD) is of great importance to wildlife officers. The ability to accurately estimate when an animal died would allow officers to tell whether legal shooting hours or seasons had been violated. This would increase their efficiency in enforcing harvest limits set by biologists as sound management goals. This study investigated three indicators of TOD of white-tailed deer (Odocoileus virginianus). Those indicators are carcass temperature, rigor mortis, and pupil diameter. Variables which might affect these indicators, such as body size, ambient temperature, carcass handling methods, etc., were also examined. Measurements of these indicators were made on 1484 deer during the 1995-96 and 1996-97 hunting seasons. Stepwise regression indicated that all three indicators were significant and that ambient temperature influenced the TOD estimation model. The indicators can be used in varying combinations but the greatest coefficient of determination (79.2%) was achieved using all three. Once the estimation model was designed, predictions of TOD were made for 28 animals for which TOD was known. No significant difference exists between the estimated and actual TOD (p=.759) and the average difference was less than 10 minutes.
© Bradley Michael Hadley
Hadley, Bradley Michael, "Estimation of Time of Death (TOD) of White-Tailed Deer: a Comparison of Three Indicators" (1997). MSU Graduate Theses. 173.